COVID-19ワクチン連続投与とSARS-CoV-2感染後の心筋炎リスク（年齢・性別）．

Risk of Myocarditis After Sequential Doses of COVID-19 Vaccine and SARS-CoV-2 Infection by Age and Sex.

抄録

背景:

心筋炎はCOVID-19ワクチン接種後よりも重症急性呼吸器症候群コロナウイルス2感染後に多く見られるが、若年層やワクチン連続投与後のリスクはあまり定かではない。

BACKGROUND: Myocarditis is more common after severe acute respiratory syndrome coronavirus 2 infection than after COVID-19 vaccination, but the risks in younger people and after sequential vaccine doses are less certain.

方法:

2020年12月1日から2021年12月15日の間にイングランドでCOVID-19を接種した13歳以上の人を対象とした自己対照ケースシリーズ研究で、年齢と性別で層別してワクチン接種と心筋炎の関連性を評価した。アデノウイルスワクチン（ChAdOx1）またはmRNAベースワクチン（BNT162b2、mRNA-1273）の連続接種後、あるいはSARS-CoV-2検査陽性後の1～28日について、100万人当たりの発症率比および心筋炎による入院または死亡の超過数を推定した。

METHODS: A self-controlled case series study of people ages 13 years or older vaccinated for COVID-19 in England between December 1, 2020, and December 15, 2021, evaluated the association between vaccination and myocarditis, stratified by age and sex. The incidence rate ratio and excess number of hospital admissions or deaths from myocarditis per million people were estimated for the 1 to 28 days after sequential doses of adenovirus (ChAdOx1) or mRNA-based (BNT162b2, mRNA-1273) vaccines, or after a positive SARS-CoV-2 test.

結果:

少なくとも1回のワクチン接種を受けた42 842 345人、3回のワクチン接種を受けた21 242 629人、ワクチン接種前後にSARS-CoV-2感染があった5934 153人であった。心筋炎は2861人（0.007％）に発生し，ワクチン接種後1～28日目に617件発生した．心筋炎のリスクは，ChAdOx1 の初回接種後 1～28 日で増加し（発生率比，1.33 [95% CI，1.09-1.62] ），BNT162b2 の初回，2 回，ブースター接種後（1.52 [95% CI，1.24-1.85]; 1.57 [95% CI，1.[95%CI，1.28-1.92]）の間で増加していた．28-1.92]，1.72[95%CI，1.33-2.22]）が，接種前または接種後の SARS-CoV-2 検査陽性後のリスク（それぞれ 11.14 [95% CI，8.64-14.36] および 5.97 [95% CI，4.54-7.87] ）より低値であった．心筋炎のリスクは，mRNA-1273 の 2 回目の投与の 1～28 日後に高くなり（11.76 [95% CI, 7.25-19.08] ），ブースター投与後も持続した（2.64 [95% CI, 1.25-5.58] ）．関連性は、すべてのワクチンで40歳未満の男性で強かった。40 歳未満の男性では，100 万人当たりの心筋炎の過剰発生数は，SARS-CoV-2 陽性後よりも mRNA-1273 の 2 回目投与後の方が多かった（97 [95% CI, 91-99] 対 16 [95% CI, 12-18])．40歳未満の女性では，100万人当たりの過剰事象の数は，mRNA-1273の2回目の投与後と検査陽性後では同程度であった（7 [95% CI, 1-9] 対 8 [95% CI, 6-8]）。

RESULTS: In 42 842 345 people receiving at least 1 dose of vaccine, 21 242 629 received 3 doses, and 5 934 153 had SARS-CoV-2 infection before or after vaccination. Myocarditis occurred in 2861 (0.007%) people, with 617 events 1 to 28 days after vaccination. Risk of myocarditis was increased in the 1 to 28 days after a first dose of ChAdOx1 (incidence rate ratio, 1.33 [95% CI, 1.09-1.62]) and a first, second, and booster dose of BNT162b2 (1.52 [95% CI, 1.24-1.85]; 1.57 [95% CI, 1.28-1.92], and 1.72 [95% CI, 1.33-2.22], respectively) but was lower than the risks after a positive SARS-CoV-2 test before or after vaccination (11.14 [95% CI, 8.64-14.36] and 5.97 [95% CI, 4.54-7.87], respectively). The risk of myocarditis was higher 1 to 28 days after a second dose of mRNA-1273 (11.76 [95% CI, 7.25-19.08]) and persisted after a booster dose (2.64 [95% CI, 1.25-5.58]). Associations were stronger in men younger than 40 years for all vaccines. In men younger than 40 years old, the number of excess myocarditis events per million people was higher after a second dose of mRNA-1273 than after a positive SARS-CoV-2 test (97 [95% CI, 91-99] versus 16 [95% CI, 12-18]). In women younger than 40 years, the number of excess events per million was similar after a second dose of mRNA-1273 and a positive test (7 [95% CI, 1-9] versus 8 [95% CI, 6-8]).

結論:

全体として，心筋炎のリスクは COVID-19 ワクチン接種後よりも SARS-CoV-2 感染後のほうが大きく，BNT162b2 mRNA ワクチンのブースター投与を含む連続投与後も緩やかなままである．しかし，ワクチン接種後の心筋炎リスクは若年男性で高く，特にmRNA-1273ワクチンの2回目接種後に高くなる．

CONCLUSIONS: Overall, the risk of myocarditis is greater after SARS-CoV-2 infection than after COVID-19 vaccination and remains modest after sequential doses including a booster dose of BNT162b2 mRNA vaccine. However, the risk of myocarditis after vaccination is higher in younger men, particularly after a second dose of the mRNA-1273 vaccine.